Simplify the following expression: $k = \dfrac{20x + 10}{10z} + \dfrac{60y}{10z}$ You can assume $x,y,z \neq 0$.
Explanation: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{20x + 10 + 60y}{10z}$ The numerator and denominator have a common factor of $10$, so we can simplify $k = \dfrac{2x + 1 + 6y}{z}$